Silicon最新文献

Bismuth-modified lead silicate glasses with composition 20PbO∙(80-x)Bi₂O₃∙xSiO₂ (10 ≤ x ≤ 40 mol%) were fabricated by classical melt-quench technique. The density (D), crystalline volume (V_C), and molar volume (V_M) values decrease with a decrease in bismuth concentration. FTIR spectra suggest the formation of [BiO₃], [BiO₆], [SiO₄], [PbO₃], and [PbO₄] structural units. The optical band gap (E_g) values for the studied glass composition are determined to be between 1.93 and 2.12 eV, while their Urbach energy (∆E) values fall between 0.14 and 0.24 eV. A decrease in values of average electronic oxide polarizability (2.84‒1.62 ų), and optical basicity (1.08‒0.64), predict the increase in the covalence nature of the Bi-O bond with the incorporation of SiO₂ in the glass network. The small metallization criterion (0.311 to 0.325) predicts the suitability of the prepared series to be utilized as nonlinear optical materials. The Z-scan approach was utilized to determine the third-order nonlinear optical characteristics, including the nonlinear absorption coefficient (α₂), nonlinear susceptibility (χ⁽³⁾), and nonlinear refractive index (η₂). Optical studies reveal that with the decrease in Bi₂O₃ content, nonbridging oxygens (NBOs) decrease leads to an increase in bandgap and a drop in the nonlinear refractive index. The dynamic range (DR) and limiting threshold values have also been reported from the optical limiting studies of the prepared glasses.

In this study, we used computer simulations of molecular dynamics to investigate structure and density heterogeneities of silica glass at glass transition temperature, 1475 K. We employed machine learning and data analysis techniques to gain a detailed understanding of the atomic-level structure of the silica glass. The investigation found that the network structure of the silica glass is composed of clusters with varying structures and densities. This structural heterogeneity with clusters is similar to the grains seen in polycrystalline materials. This observation indicates that silica glass can exist in multiple amorphous structural forms, analogous to polymorphism in crystalline materials. Additionally, we applied detailed 3D visualizations to effectively represent the structural characteristics of the silica glass. These visualizations provided valuable insights into the complex and heterogeneous nature of the silica network.

Silicon (Si) is essential to the nutritional status of many monocot and dicot plant species, and it aids them in resisting abiotic and biotic challenges in various ways. This article explained the progress in exploring silicon-mediated resistance to sugarcane insect pests, its role in increasing juice quality attributes and cane production, the silicon status of soil and uptake by sugarcane plant, and the mechanisms involved. The aim is to determine the influence of different sources of Si application on the availability of silicon in soil, silicon uptake by plants, silicon effect in minimizing biotic stresses such as defence against sugarcane insect pest herbivory along with its effect on sugarcane yield in terms of juice and other component traits. There are two basic modes of action: enhanced physical or mechanical barriers and biochemical or molecular mechanisms that activate plant defence responses via bitrophic (plant-herbivore) interactions and tritrophic (plant-herbivore-natural enemy) interactions. By integrating the data reported in this research, a comprehensive understanding of the relationship between various sources of silicon treatments, increased sugarcane plant resistance and decreased sugarcane insect pest damage might be attained.

Deep and ultra-deep oil and gas resources have considerable potential and are now the primary resources to be explored and developed. However, the formation conditions get more harsh and challenging as the drilling depth increases. At 150°C, the majority of natural polymers start to degrade thermally, whereas synthetic polymers perform exceptionally well under even higher temperatures. Based on the excellent thermal stability of polysiloxane in other research areas, a modified siloxane monomer (F-PDMS) was synthesized and copolymerized with acrylamide (AM), 2-acrylamido-2-methylpropane sulfonic acid (AMPS) and N-vinyl caprolactam (NVCL) to prepare a novel modified polysiloxane filtrate reducer (F-LS) with high-temperature resistance. The structure of products was characterized by Fourier transform infrared spectroscopy and the proton nuclear magnetic resonance, and their thermal stability was investigated using thermogravimetry. Furthermore, the rheological properties, filtration reduction, and inhibition performance of F-LS in base mud were evaluated. The results showed that after rolling at 220°C for 16 h, the API (American Petroleum Institute) filtrate loss (ambient temperature, 0.69 MPa) of 1% F-LS was only 8.8 mL, and the high-temperature (220 °C) and high-pressure (3.5 MPa) filtration was 26.8 mL, and the linear swelling rate of API filtrate liquid was dropped from 12.57% to 9.74%. Compared to Driscald and Polydrill, the effectiveness of filtrate loss reduction of F-LS was superior. The filtration control mechanism of F-LS was revealed based on the scanning electron microscopy analysis, particle size analysis, and Zeta potential test. F-LS could absorb on the clay surface and cover the pores on the surface of filter cake, and make the latter more condensed. Particularly, F-LS increased the absolute value of Zeta potential of clay particles, thus increasing their double-layer repulsion, and hydration film thickness, maintaining the proportion of submicron particles, thereby improving the stability of rheology and filtration of drilling fluids under harsh conditions.

Graphical Abstract

The aim of this study is to examine a low-power, InAs/Si hetero-gate oxide double-gate Tunnel field effect transistor (H-DM-DG-InAs-TFET) for high frequency application and to determine how trap charges (ITCs) affect the DC characteristics and analog/RF electrical performance metrics of the device. It is unfeasible to disregard the trap charges because the device's performance and reliability are negatively impacted by the buildup of trap charges at the interface between the semiconductor and oxide. Hence, an in-depth analysis of the performance characteristics of the proposed device, a InAs/Si hetero-gate oxide double-gate Tunnel FET (H-DM-DG-InAs-TFET), is conducted in this work to ascertain the impact of interface trap charges (ITCs). Comparison study of proposed device with dual metal gate Si Tunnel Field Effect Transistor (DM-DG-Si-TFET) is conducted. The proposed device is capable of effortlessly carrying enhanced ON current (1.54 × 10^–3 A/µm) and exhibits improved current ratio (1.63 × 10¹¹). To ascertain the device's suitability for low-power applications, its threshold voltage is determined by employing a constant current methodology. An improvement in threshold voltage (0.17 V) is noted. According to the study, the efficacy of the proposed device was enhanced due to the dielectric engineering performed on the oxide layer. Further investigation is conducted into the impact of ITCs on linearity parameters, as advanced communication device necessitates linear responses. The comparison with the DM-DG-Si-TFET reveals that the proposed TFET has virtually no distortion and a negligible impact on the linearity metrics. This indicates that the proposed TFET can be utilised in extremely low-power, high-frequency electrical devices.

Nano SiO₂ has been effectively utilized as a catalyst in the synthesis of new benzimidazoles. The resulting benzimidazoles have been characterized using ¹H and ¹³C NMR spectroscopy, confirming their structure and purity. This nano catalyst is notable for its ability to produce higher product yields, reduce reaction times, and operate in environmentally friendly reaction media. Additionally, it is versatile in accommodating a wide range of substrates, making it a highly efficient and sustainable option for benzimidazole synthesis. The single crystal X-ray analysis of 2-(naphthalen-1-yl)-1-phenyl-1H-benzo[d]imidazole (1) has been performed and discussed. Compound 1 exhibits substantially planar naphthalene ring system [maximum deviation = 0.0254 (6) A º] and benzimidazole unit [maximum deviation = 0.0258 (6) A º]. A dihedral angle of 61.955 (17) ˚ is made by them. The imidazole ring forms a dihedral angle of 61.73 (4) ˚ with the phenyl ring. The benzimidazoles2-(4-(difluoromethyl)phenyl)-1-phenyl-1H-benzo[d]imidazole (2), 1-(4-chlorobenzyl)-2-(4-chlorophenyl)-1H-benzo[d]imidazole (4) and 1-(4-bromobenzyl)-2-(4-bromophenyl)-1H-benzo[d]imidazole (5) are more active against S.aureus and S.typhi, for antibacterial studies. In comparison to the usual medication, benimidazoles 2 and 4 exhibit greater activity against A. flavus and C. albicans in antifungal tests.

This study reports the deposition of amorphous hydrogenated silicon thin films by radio frequency magnetron sputtering and their optical characterization by UV–visible spectroscopy and FTIR Spectroscopy. Structural characterization and morphological studies are also performed. It investigates the effect of process factors such as RF power, hydrogen concentration, and deposition temperature on the optical properties of the deposited films. The impact of process parameters like RF power, hydrogen flow, and substrate temperature on the bandgap, refractive index and hydrogen concentration has been studied. The study draws a comparison due to the crucial interactions among RF power, hydrogen flow, and substrate temperature which affect the optical and structural characteristics of a-Si:H thin films. For a particular application, the critical control of these parameters is necessary to provide the requisite film qualities. The films prepared with optimized deposition parameters of RF power of 80 W, hydrogen flow of 5 sccm, and deposition temperature of 150 °C, resulted in a bandgap value of 1.80 eV, refractive index of 2.3, and hydrogen concentration of 5.15% which can be useful as absorber layer in photovoltaic applications. Despite the amorphous nature of all the films, achieving a high-quality a-Si:H thin film requires control over the growth structures, where hydrogen plays a crucial role in passivating the defects.

This study investigates the impact of different materials and dental implant-abutment interface models on bone shielding effects, micro-gap formation, and torque loss in abutment screws. Von-Misses stress analysis identifies the MTC model as exhibiting maximum stress transfer for titanium alloy and CFR-PEEK, while the IHC model dominates for C2 bio-composite dental implants. Although material type has minimal influence on stress shielding, the implant-abutment interface model proves crucial. Micro-gap analysis reveals the Optimized dental implant consistently displaying minimal micro-gaps across materials, while the NLD model consistently exhibits maximum micro-gaps. Both material type and interface model significantly influence micro-gap formation. Torque loss in abutment screws varies, with the MTC model consistently experiencing high torque loss and IHC showing minimal loss. The study underscores the importance of considering material properties and interface models in dental implant design, offering valuable insights for the development of reliable dental prosthetics.

Two sets of glasses were prepared by rapid melt quench method in the glass system (Eu₂O₃)_x (Na₂O)_0.1 (B₂O₃)_0.6 (SLS)_0.3-x and (Eu₂O₃)_0.01 (Na₂O)_0.1 (B₂O₃)_0.6 (SLS)_0.29-y (MgSO₄)_y with x and y = 0, 0.005, 0.01, 0.03, and 0.05 mol% to check the effect of MgSO₄ inclusion on the glass properties. XRF analysis confirmed the chemical composition of the SLS glass to be 70.81wt% SiO₂. The addition of MgSO₄ to NaSBEu glasses lowered the sample’s density due to the lower density of Mg (1.738 g/cm³), whereas Eu has a density of 5.25 g/cm³. Adding MgSO₄ to NaSBEu glasses raised the band gap values from 3.85 to 3.90 eV and the indirect band gap from 3.22 to 3.23 eV for NaSBEu0.005. The absorption peaks result from the trigonal BO₃ bond's relaxation, which causes asymmetric vibrational stretching of the borate. The primary basis for the network structure of these glass samples is the arrangement of BO₃ and BO₄ units in various structural groupings. The sharpness of the IR absorption peaks increases with the addition of MgSO₄.